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Found some Hypereutectic pistons not that expensive!

Cubes

By Cubes,
in Engines & Forced Induction

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Cubes Grand Master

Cubes

Posted
  • Author
Posted

Thats true..

had any one thought about the possibility that the reason why we can run so much boost and power with the standard internals compared to the VL's is that the RB20/25/26 motors have oil squirters?

Cubes Grand Master

Cubes

Posted
  • Author
Posted

Sounds good... I'm going to start looking in to how a RB30 bottom end bolts in to a R32 GTR.

I'm tired of 2wd no traction. :(

I am probably dreaming still as my budget is max 25k. All the GTR's around here I have seen are 35k. And even then the one down on Anzac Highway (Silver One) has had a few bingles as the gaps etc don't line up and the under body has been freshly painted. Some thing just didn't look right with it.

Xeron Enthusiast

Xeron

Posted
Posted

Ive said this before in previous threads. If u get hyper pistons, i sure as hell hope u dont drive in summer, cause a just a few seconds of ping and u can blow a hole in em. And hey there also alot more likely to ping too due to the higher silica content refecting more heat into the combustion chamber.

Cheap

Fast

Reliable

Pick any 2.

Sydneykid Grand Master

Sydneykid

Posted
Posted

Hi guys, Its pretty simple really, an RB30 being a 2 valve engine does not flow as well as RB20/25/26's with their 4 valve heads. So to make decent power they have to run a lot of boost, rule of thumb 5 to 6 psi more to make the same power. Such high boost requires lower compression ratios, rule of thumb 0.5 lower for the same power.

My experience, comparing compression ratios for 2 and 4 valve heads is a waste of time. On the flow bench we typically see 30% more flow out of 4 valve heads with similar capacity.

Hope that adds to the discussion.

GTS20X Enthusiast

GTS20X

Posted
Posted

Another thing with Hypereutectic pistons is they tend to shatter rather than just break or crack ring lands like cast or forged pistons. Also some forged pistons also have a high silicone content so be careful if your thinking of running Nitrous.

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